Question

A particular sample of air is 2.5% water vapor express the concentration of water vapor in parts per million

Answer 1

Answer:

                     25000 ppm

Explanation:

Parts Per Million is defined as the number of parts of a solute per one million parts of a solution.

                  ppm  =  (Weight of Solute / Weight of Solution) × 10⁶   ---(1)

Let us suppose that the air (solution) weights 100 grams, then 2.5 % of water vapors will have following mass,

Mass of Vapors g / 100 g × 100  =  2.5

Or,

Mass of Vapors = 2.5 × 100 / 100

Mass of Vapors  =  2.5 g

Hence, mass of water vapors is 2.5 g.

Now, putting mass of water vapors and air in eq. 1,

                  ppm  =  (2.5 / 100) × 10⁶

                 ppm  =  25000